Hitherto, for example, a solid type radius end mill disclosed in Patent Document 1 below has been used at the time of performing a face milling process or a side finishing process on, for example, a workpiece such as a die.
Further, an indexable radius end mill including a columnar holder body which is rotated about a rotation center axis and an insert which is detachably attached to a slit formed on a tip end portion of the holder body and is disposed so that a cutting edge portion protrudes outward in a radial direction and toward the front end from the tip end portion of the holder body is known.
The cutting edge portion of the indexable radius end mill includes an outer peripheral cutting edge which extends along a rotation center axis direction, a bottom cutting edge which extends along a radial direction orthogonal to the rotation center axis, and a cutting edge of a corner R which connects an outer end of the bottom cutting edge in the radial direction to a front end of the outer peripheral cutting edge in the rotation center axis direction and is formed in an arc shape to protrude outward from the periphery of the tip end portion of the holder body.